Ultrasound-assisted regioselective ring opening of epoxides with nitrogen heterocycles using...
Zakeri, Masoumeh; Nasef, Mohamed; Abouzari-Lotf, Ebrahim; Haghi, Hoda
2015-04-14 00:00:00
Imidazolium and N-methyl-2-pyrrolidonium ionic liquids under ultrasound irradiation were developed as a green and expeditious approach for C--alkylation and N-alkylation of the nitrogen heterocycles including indoles and imidazoles with aliphatic and aromatic epoxides. Ionic liquids were used with a dual role of catalyst and solvent. The highest yield (85 %) was obtained with N-methyl-2-pyrrolidonium dihydrogen phosphate [H-NMP]H2PO4 as a pyrrolidonium ionic liquid under ultrasound at 50 kHz, with a reaction time of 60 min and reaction temperature of 60 °C. The combination of ionic liquids and ultrasonic irradiation was found to be an effective, green and eco-friendly method for alkylation of indoles and imidazoles.
http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.pngResearch on Chemical IntermediatesSpringer Journalshttp://www.deepdyve.com/lp/springer-journals/ultrasound-assisted-regioselective-ring-opening-of-epoxides-with-S6AV1EIfOD

Abstract

Imidazolium and N-methyl-2-pyrrolidonium ionic liquids under ultrasound irradiation were developed as a green and expeditious approach for C--alkylation and N-alkylation of the nitrogen heterocycles including indoles and imidazoles with aliphatic and aromatic epoxides. Ionic liquids were used with a dual role of catalyst and solvent. The highest yield (85 %) was obtained with N-methyl-2-pyrrolidonium dihydrogen phosphate [H-NMP]H2PO4 as a pyrrolidonium ionic liquid under ultrasound at 50 kHz, with a reaction time of 60 min and reaction temperature of 60 °C. The combination of ionic liquids and ultrasonic irradiation was found to be an effective, green and eco-friendly method for alkylation of indoles and imidazoles.